How to Reveal a Plant’s Vascular System

Are you looking for a WOW-factor experiment? Then this is the one! For maximum impact, I suggest the next-level option with the highlighter and black light.

Plants are more complicated than they appear on the surface. But did you know you can reveal the framework of plant’s physiology in a simple experiment at home?

What You Need:

• Cups or Test Tubes
• Food Coloring
• Water
• Leafy Celery or Carnations (other options: lettuce, gerberas & argyranthemums)
• Scissors
• Yellow Highlighter (optional/next level)
• Black Light Flashlight (optional/next level)

Directions

Step 1

In a cup, mix 15 drops of food coloring of your choice with a half cup of water.

Step 2

Cut at least two inches off the ends of the celery stalks or carnation stems.

Note: Hold the carnation stems under water while trimming them, and then quickly place them in the glass of water. This prevents air bubbles from forming in the plant’s vascular system. Learn more about why this is important in the explanation below.

Step 3

Leave the plants in the dyed water overnight. Check on them the following day and you’ll see the plant’s inner transport system of water revealed.

Optional/Next Level Experiment

If you want to take your experiment to the next level, then you can use highlighter ink instead of food coloring. Pull the plug out of a highlighter with pliers. Drop the ink sponge tube in a half cup of water. Leave the plants in the water until nighttime, except this time you’ll reveal the plant’s vascular system by shining a black light flashlight on the plant. The phosphors in the highlighter ink that the plants pulled into their system will glow under ultra violet light!

Explanation

The vascular system of plants is made of straw-like tubes called xylem and phloem. Phloem transports the food made by chlorophyll in the leaves throughout the plant. Xylem moves the water and nutrients from the roots to the stems and leaves.

The human vascular system has a heart to pump our blood, but plants have a different mechanism to move fluids and nutrients. The water defies gravity and travels upward because of the properties of water and capillary action.

Water molecules are attracted to one another and as a single molecule evaporates from the leaf, each water molecule in the chain moves up in line and the roots pull in another water molecule to replace each one lost.  This continuous chain of water is key to the process, and is the reason you don’t want an air bubble sucked up by a flower stem in your bouquet.

How did your colorful, glowing plant experiments turn out? Share your photos on my Tamawi Facebook page or on Instagram with #tamawi.

Here are more experiments to try at home!